In optical communications systems and networks, optical fiber cables are used to interconnect components and to carry optical signals between the components. The optical fiber cables have optical fiber connectors on each end that hold the ends of the optical fibers of the cable. Optical fiber cables may have a single optical fiber or multiple fibers. Optical fiber cables that have multiple optical fibers are terminated on their ends with multi-optical fiber (MOF) connectors. MOF connectors are adapted to mate with multi-channel optical communications modules, referred to herein as parallel optical communications modules. A parallel optical communications module is a device that includes multiple optoelectronic devices, such as, for example, laser diodes, light-emitting diodes (LEDs) and/or photodiodes, and various electrical components, such as, for example, laser diode driver integrated circuits (ICs), transimpedance amplifiers (TIAs) and/or receiver ICs.
Optical signals generated by the laser diodes or LEDs are optically coupled by an optics system of the module into the MOF connector connected thereto, which then couples the signals into respective ends of respective optical fibers held in the MOF connector. Optical signals passing out of ends of optical fibers held in the MOF connector are coupled by the optics system of the parallel optical communications module onto respective photodiodes of the module.
MOF connectors are available in a variety of types, styles and configurations, as are the parallel optical communications modules with which they are used. MOF connectors of all types, styles and configurations perform the same function, namely, the function of mechanically coupling the ends of the fibers held therein with the respective mated parallel optical communications modules. Mating features of the MOF connector engage mating features of the parallel optical communications module to mechanically couple the connector with the module in a way that optically aligns the optical pathways of the connector with the optical pathways of the module.
There are times when it is necessary or desirable to interface an MOF connector of one optical fiber cable with an MOF connector of another optical fiber cable. For example, it may be necessary or desirable to extend the length of an optical link by joining multiple optical fiber cables together end to end. For this reason, some MOF connectors are designed to be able to mate with one another in addition to being designed to mate with a parallel optical communications module. For example, female mating features (e.g., cylindrical holes) of one of the MOF connectors may be shaped, sized and positioned to receive male mating features (e.g., pins) of another MOF connector. In such cases, the mating of the MOF connectors brings the ends of the optical fibers held in one of the MOF connectors into proximity and alignment with the respective ends of the optical fibers held in the other MOF connector. In some cases, a receptacle or adapter is used to hold the MOF connectors and maintain them in the mated arrangement.
Some manufacturers of MOF connectors also manufacture adapters that are designed to interconnect the MOF connectors. For example, US Conec, a company headquartered in Hickory, North Carolina, manufactures an adapter for interconnecting two MOF connectors known in the industry as MTP® connectors, which are also manufactured by US Conec. MTP® connectors have multi-fiber ferrules that hold the ends of the fibers. The adapter has receptacles formed in opposite sides thereof into which respective MTP® connectors are inserted. When the connectors are inserted into the receptacles of the adapter, the end faces of the multi-fiber ferrules abut one another in an aligned configuration such that the respective fiber end faces held in the abutting ferrules are precisely aligned with one another. The precise alignment of the respective fiber end faces is important in preventing optical losses from occurring as optical signals are coupled from the fiber end faces held in one ferrule into the opposing fiber end faces held in the other ferrule.
Although such adapters work well for their intended purposes, they are not suitable for use with all types of MOF connectors. For example, such adapters are not suitable for use with MOF connectors in which the optical pathways turn, or bend, in between the end faces of the optical fibers held therein and the output facet of the connector. For example, MOF connectors exist that bend the optical pathways by a non-zero angle (e.g., 90°) in between the ends of the optical fibers and the output facet of the MOF connector. Currently, suitable adapters for easily, quickly and precisely interfacing such connectors do not exist. Accordingly, a need exists for such an adapter.